Automatic switch



Feb. 5, 1929. 1,700,890

c. H. HoDGKlNs E1- AL AUTOMATIC swITcH Filed March 23. 1922 ATTORNEYChar/ea h. h'ody/rins and Patented Feb. 5, 1929.

UNITED STATES maar@ PATENT: OFFICE.

vCHARLES H. H oDGKINs AND CHARLES MCL. Moss, or PITTSBURGH,PENNSYLVANIA,

AssreNoRs'To WESTINGHOUSE ELncTR-rc AND MANUFACTURING coMrANY, A con-PORATION OF PENNSYLVANIA.

Application led March 23, 1922. Serial Ne. 546,108., 'Y

Our invention relatesto automaticelect-rie switches` and particularly.to those of the type wherein a protective means is employed to causeactuation thereof uponthe occur-- rence of predetermined' conditions inthecir- Ycuit that is controlled thereby.

The object of our invention is to -combine, with a switch, means forcausing the same Ato be operated, either upon thefalling of the currentin a circuit below a predetermined value or upon the occurrence of anoverload on the circuit, and to embody such protective feature in asimple and compact form of construction. Y j

Our invention is-especially applicable for use in connection withelectrically operated domestic appliances and may replace the ordinarypush-button or'snap switches that vareusually incorporated insuchappliances` As shown in the'accompanying drawings,

Figure 1 is a View, partially'inside elevation and partially in-section,otra circuit interrupter embodying 'our invention, and

Fig. 2is a view taken onthe line AITV-1I T he Switch controls a supplycircuit 3 for a motor 4 and is mountedupon a base 5 t0 which contactmembers 6 are.secured. A bridging contact member 7is secured to, andinsulated from, a non-magnetic operating rod S that is provided, at.its' upper end, with a push button 5). The rod 8 is biased upward` ly bya compression spring 10, to normally maintain the bridging member 7 outof engagement with the Contact member (i.

An electron'iagnet 11 is connected in series with the circuit 3 and isprovided with a core member 12, through which the rod 8 extends. Abracket 14- servesto p'ivotally support ar- .matures 15 and 16, thearmature 15 being sufficiently small so that, when saturated by the fiuxfrom the clectromagnet, the attraction thereof does not increase1 inproportion to the current How, to the extent of the increase inattraction of the armature 16.

The armature 15 is engaged, on its upper and lower sides, by thepins 18and 19, respectively, that extend through the rod 8 and there is atendency for it to be biased out. of operative engagement with the core12 by the action of the spring 10.

Upon the depression of the button 9, th

jcircuit is closedfacrossl the contact members '6, and thearmature, 15`fis broughtintoengft-gement with. the core-1 2 and maintained 55 insuchposition, against thefactionof the A.spring 10,-so long as the.current .in the circuit 3-does not fall below` a value sutcient .tomaintain enough energyin the electromagnet to hold the.brid0ing- ;member 7 in'closed 60 position. The switch` may .be. normally ,openedbydepressing abutton 20, ,whereupon the electromagnet- 11 .v vi1lofcourse, be deenergized.

The coil 11 is 22 that. may consistof a brass or copper ring.

.The shading coil-,is necessary onlywhen used .in connection with ,asingle-phase. alternating current. and functions; in the usual manner,

to provide. substantiallypsteady pullon the .n

armaturefl.

1- In ca se an overloadpccnrs n .thexcircuit ,3, the armature 15gwillbecoinclsaturated. ,and the armature lbe energized? .totsuclrpoint thatit willfbegactuated tirstgintofen age-r ment withafpinthatfextends{throug rthe .rod 8 :and `,th en finto, 'engagementwithA the lower end olf'tliecoreneinber;12,. thus overcoming the forceexerted. bythe armature 15 on the pin 19 and movingrth'e' rodA 8'vupward- 80 ly to interrupt theA cireuitf screw 24 is provided toregulate the .distancebetween the armature 16 andA the 'core 12forcausing the actuation ofsuch armature tolanj,v

desired degree of overload in the circuit.

From vthe foregoing, it ivill be. seen that we provide a compact ande'liicient form of protective device that is automatically'operable toopen a circuit-under abnormal or predetermined conditions of eitheroverload or low voltage. l

Various changes in detail and general arrangement may be readily madeWit-hout departing from the spirit and scope of the invention, asdefined by the accompanyingr o5 claims.

lVe claim as our invention 1 1. The combination witha.circuitinterrupter and an operatingr rod therefor, ofmeans foryicldingly maintaining the interruptor in open position, anelectromagnet, an armature co-operating with one side of the said magnetand having engagement with the said rod to hold it in closed position,and a second provided coil 65 armature co-operating with the other sideof the magnet and also having connection with the rod, to nievethe-first named armature out of engagement with the electromagnet upon.

the occurrence of an increase of current in the reci-mangue.'

2." The combii'iatio'n with a circuit interrupter and an operating rodtherefor, of means for yieldingly maintaining'the inter;- rupter in openposit-ion, an electromagnet, an armature co-operatingwith one side ofthe said magnet and having engagement with the said rod, to' hold it inclosed position. a second armature cooperating with the other side ofthe-magnet and also having connection w1lh the rod,I to move lthe firstnamed armature out of engagement with the eleetromagnet upon theoccurrence of an increase of current in the electromagnet, and means foradjustably supporting the second named armature in spaced relation tothe magnet'.

3.Tlie combination with a circuit interrnpter'normallybiased to openposition, of an electromagnet, an armature having connection `with theIinterruptor to hold it in closed position'ivhen the current in theelectromag 'net exceeds a predetermined value, and a second armaturehaving connection With the interrupter to moveitto ope` position and torelease the firstarmature upon the occurrence of a current flow in theelectromagnet in eX- Vcess ofthe said predetermined value.

crrrence of 'a current flow in the clectroinag net in excess of apredetermined value.

5. The combination with a circuit interrupter, of actuating meanstherefor compris ing an electromagnet, an armature manually operableinto and out of engagemen l1 with the electromagnet and having,connection with the interruptor to hold it closed during the presence ofnormal fioiv of current in the electromagnet and a second armaturehaving lostmotion connect-ion with the first named armature and normallyoccupying an inoperative position, actuated to move the Erst-namedarmature to inoperative position to open the circuit interrupter uponthe occurrence of an increase in current to a. predetermined amount.

6., The combination with al circuit interrupter, of actuating meanstherefor comprisin T an electromagnet, an armature manually operableinto and out of engagement with the electro-magnet and' havinglconnection with the interruptor to hold it closed during the presence ofa normal flow of current, means for biasing the inter'rupter against theholding force of the electromagneta second armature havingflostmotioiiconnection' 'with the first. named armature and actuated by theelectromagnet. u onzin, crease oi current ther'ento'noife t rst""d'arrdait'nrend th' Circuit tiruiie Ltd slerat'postion.

l L Ihecombination With a circuit intering with the 'electromagnetlndhaving' co'nnection Withthe intewu'pterto hold it closed during thepresence of normal flow olfcn-rrent in the elec'trornaighet,l'secondaimature having lost-motion connection 'the 'firstnamed armatuneand 'normally occupying fan inoperative lposition adaptedtofbe-att'rated upon theoceurrefiee of in the' e'Iecto inoperativeposition: i -V K 9. 'In SWitCiig-ppaiat, tli Cnbnatifn with a circuitir'iterriptr," of means for; 'closing the" 'interi-tiptel',magneteineansf-forglioldingthe interruptor closed, and mearisfcen---"trolled by" 'predetermined 'Conditions 'in the magnetic meansl forovercoming the magnetic for of the holdii1g'-nieans and'for' moving thecircuit interrupte tov open: position.'

10. In 'switch-ing apparatugthe combination with a circuit interrupter,of means for closing the interruptor,fmagnetic means for holding theinte'u-p'ter closed and an armature actuated upon vthe occurrence of anoverload in the magnetic means, for moving the interruptor t-oopenposition after releasing the holding means.l

11. In switching apparatus, the combination with a circuit interrupt-er,of means for closing the interruptor, an electromagnet, an-

armature for holdin@ the interruptor closed and means controlled bypredetermined conditions in the electromagnet for overcoming themagnetic force of the holding means and for moving the circuitinterrupter to openA position.

12. In switching apparatus, the combination with a circuit interruptor,of mean-s normally biasing the switch to open position, electromagneticmeans for holding the interrupter closed during the presen-ce of apredetermined current value, and electromagnetic means actuated upon theoccurrence of llO an increase of current for neutralizing the force otthe said holding lneans causing its release.

13. The combination with a. circuit interruptor, ot' an electromagnet,an armature energized b v the electron'iagnet to hold the interruptor inone position, a second armature energized by the electromagnet torcausing movement of the iii-st said armature and the interruptor toanother position when an increase in current flows through the magnet.

14. The combination with a. circuit interrupter, of an electromagnet, anarmature energized by the electromagnetto hold the inrrrnpter in oneposition, a second armature energized by the elertromagnet for causing;lmovement o t the irst said armature and the interrupter to anotherposition, the iirstnamed armature beingr of such size that it becomessaturated upon an increase of current in the electromagnet.

15. The combination with a circuit interruptor, of an electromagnet, anarmature energized by the electroinagnet to hold the interrupter in oneposition, a second armature energized by the electromagnet for causing'movement ot the iii-st said armature and the interrupter to anotherposition, the tirati-named armature being of such size that it becomessaturated and released upon an increase of current in the electromagnetdue to the .second named armature being more strongy attracted by suchincrease.

16. 'the combination with a circuit interrnpter, of an electroinaggnet,an armature energized by the electromagnet to hold the interruptor inone position, a second armature energized by the electromagnet forcausing movement ot the first said armature and the interruptor toanother position, the firstnamed armature being` oi such size that itbecomes saturated upon an increase of current in the eiectromagnet, thetwo armatures being so connected that, upon movement of one ot' themtoward the electromagnet, the other is moved away from said magnet.

l?. The combination with a magneticallyactuated circuit interrupter, ofan arn'iature normally energized to hold the interrupter in oneposition, a second armature in position to be energized for causingmovement of the iirst said armature and the interrupter to anotherposition and means whereby, upon saturation oit' the tirst namedarmature, the said second armature is actuated.

In testimony whereof, We have hereunto subscribed our naines this 21stday ot March,

CHARLES H. HODGKINS. CHARLES MCL. MOSS.

